The aging behaviour of novel MV-busbar connections

Environmentally independent switchgears are widely used in distribution networks. For GIS applications, a replacement of switchgear panels without gas handling at site is a preferred solution. In order to achieve such a solution, a flexible connecting system for the busbar is required. The busbar connection itself has to fulfill several requirements: carrying nominal currents and over-currents, guaranteeing a stable contract resistance over the lifetime, to adjust misalignments of the busbar positions and enabling the assembly and disassembly of the busbar. This article describes a novel solution for a flexible busbar connector. The proposed solution is mainly dedicated to higher installation flexibility without any negative impacts on the ageing performance of the electrical contact over its lifetime. The ageing of the contact system was investigated with a reference busbar assembly and an accelerated test procedure.